The present invention relates to a connector for use in electric and electronic appliances such as mobile devices, and more particularly to a connector which achieves extremely narrow pitches for a connecting object such as a flexible printed circuit board, flexible flat cable and the like.
In general, connectors for use in electric and electronic appliances such as mobile devices and the like are much thinner and having contacts arranged in extremely narrow pitches (so-called lighter and more compact connector). Such a connector of one type mainly comprises a housing and contacts, and a flexible printed circuit board is inserted into the housing to force the circuit board into contact with contact portions of the contacts (so-called “non-zero-insertion force (NZIF)” type). Moreover, another type connector mainly comprises a housing, contacts and a member so that a flexible printed circuit board is embraced between the housing and the member (so-called “zero-insertion force (ZIF)” type). Various methods may be envisioned for holding a flexible printed circuit board by means of the housing and the member. In many cases, there have been constructions in which after a flexible printed circuit board has been inserted into a housing, a member is inserted into the housing to press the circuit board against the contacts. In recent years, however, a type having a member to be rotated on the side of a fitting opening (front lock type) and a type having a member to be rotated on the opposite side of a fitting opening (rear lock type) have been increasingly being used. On the other hand, depending upon customer's demands or for achieving the narrow pitches, it may be sometimes unavoidable that connection portions of contacts should be located on the side of a fitting opening of a housing into which a flexible printed circuit board is inserted.
A housing may be usually formed with a required number of inserting holes for inserting contacts, and a fitting opening into which a flexible printed circuit board is inserted.
In general, contacts each comprise a contact portion adapted to contact a flexible printed circuit board, a connection portion to be connected to a substrate or the like, and a fixed portion to be fixed to the housing. These contacts may be fixed to the housing as by press-fitting.
In order to connect between a substrate and a connecting object such as a flexible printed circuit board and the like, hitherto, the connectors as described above have generally been used.
As examples of relevant connectors, incorporated herein are Japanese Utility Model Application Opened No. H6-60,983 (1994) of a zero-insertion fore (ZIF) type connector (Patent Literature 1), Japanese Patent Application Opened No. H5-326,084 (1993) of a non-zero-insertion force (NZIF) type connector (Patent Literature 2), Japanese Patent Application Opened No. 2002-270,290 of a so-called rear lock type connector (Patent Literature 3), and Japanese Patent Application Opened No. 2004-206,987 of a connector using contacts of two kinds (Patent Literature 4).
Patent Literature 1
For example, Japanese Utility Model Application Opened No. H6-60,983/1994 discloses connectors of the zero-insertion force (ZIF) type. According to the abstract of the Japanese Utility Model, this invention relates to a connector having a slider for a printed circuit board for use in a narrow space in an electronic or communication appliance. The slider of a connector is formed at ends of both sides with U-shaped arms with their proximal ends fixed to the slider as guiding means when being inserted into a housing. The U-shaped arms are each provided on its opening side with a projection and formed with a notch such that the opening end is visible from the inserting side. The housing is provided at both the ends with projections having an oblique surface adapted to engage the projection of the slider. When the slider together with connection terminals of a flexible printed circuit board is inserted into the housing, the projections of the slider ride over the projections having the oblique surface of the housing so that the opening ends of the U-shaped arms of the slider are temporarily spread outwardly and then returned to their normal positions when the insertion has been completed.
Patent Literature 2
According to the abstract of the Japanese Patent Application Opened No. H5-326,084, this invention has an object to provide a connector for a circuit board, which is capable of securely connecting a circuit board having along an edge signal inputting and outputting terminals particularly miniaturized and arranged with narrower pitches without causing any positional deviation, thereby improving productivity. Disclosed in this Patent Literature 2 is a connector for a circuit board, including jack terminals provided at locations corresponding to a plurality of signal inputting and outputting terminals formed in a row along an edge of the circuit board and to be individually connected to the signal inputting and outputting terminals, and an insulator for arranging these jack terminals, and after the circuit board has been inserted into an opening of the insulator on the jack terminal contact side from the signal inputting and outputting terminal forming side, said circuit board being pushed and moved to the jack terminal contact side to cause the contacts to be connected to the corresponding signal inputting and outputting terminals, wherein in the region of the insulator into which the circuit board is inserted, there are provided means for positioning the circuit board inserted to a predetermined position at least on both the sides in the width direction of the signal inputting and outputting terminal forming region.
Patent Literature 3
According to the abstract of the Japanese Patent Application Opened No. 2002-270,290, this invention has an object to provide a reduced overall height connector having an actuator which is actuated by a slight operating force and capable of enlarging moving distances of contacts to securely performing connection. Disclosed is a connector comprising an actuator having cam portions and an actuating portion, between both the portions being formed with relief grooves into which tips of spring potions of the contacts are inserted and removed, so that when the actuator is rotated about its fulcrum through 90° in a clockwise direction, the cam portions cause the spring portions and connecting spring portions of the respective contacts to be elastically deformed to embrace a flexible printed circuit board between projections of the contact portions, with the result that patterns of the flexible printed circuit board are connected to a printed substrate through terminals of the contacts, and an insulator having a ceiling portion covering the contact portions of the respective contacts and formed in the lower portion of the front side of the ceiling portion with a guide portion for inserting the flexible printed circuit board into the connector.
Patent Literature 4
According to the abstract of the Japanese Patent Application Opened No. 2004-206,987, this invention has an object to provide a connector for accommodating narrowed pitches and for tolerating a flexible printed circuit board having contact portions on both surfaces. Disclosed is a connector including a required number of contacts each having a contact portion adapted to contact a flexible printed circuit board, and a housing for holding and fixing the contacts and having a fitting opening for inserting a flexible printed circuit board, wherein when the flexible printed circuit board has contact portions on both front and rear surfaces, contacts of two kinds are used in a manner such that the contacts of one kind are inserted into the housing from the opposite side of the fitting opening so as to permit their contact portions to contact the contact portions on the front surface of the circuit board, and the contacts of the other kind are inserted into the housing from the side of the fitting opening so as to permit their contact portions to contact the contact portions on the rear surface of the circuit board.
In recent years, with the miniaturization of electric and electronic appliances, the need for connectors of this kind to be more miniaturized has become stronger. On the other hand, the requirement for narrower pitches has become stronger, and at the same time the requirement for signal density to increase (high density) has been stronger.
However, the connectors hitherto used and the connectors disclosed in the Patent Literatures 1 to 4 could not achieve narrow pitches less than 0.25 mm, and it would be impossible to achieve the high density, while maintaining narrow pitches. These problems remain to be solved.